In such a type of navigation, various objects (pieces of information) are arranged on a map. Particularly in the case of facility icons, a huge number of icons are displayed on a map, and there are cases in which facility icons overlap each other, and facility icons cover a guidance route. Accordingly, there may be case in which information important during travel, particularly a guidance route including an intersection where the user should make a right or left turn is covered by a facility icon, the guidance route being one of the most important guidance routes provided for the user.
For example, a conventional technique disclosed by patent reference 1 relates to a guidance device based on building shape maps, for providing guidance on roads by displaying a building shape map in which house shapes and roads are drawn. The guidance device searches for landmark information about landmarks located around a specific point, and displays the landmarks on a building shape map.
The guidance device also sets a region extending from the current position in the traveling direction according to the vehicle speed, searches for landmark information about landmarks located within a region with a predetermined angle and at a distance from the current position in the traveling direction, and landmark information about landmarks located around an intersection for guidance, and displays the pieces of landmark information as landmarks.
According to a conventional technique disclosed by patent reference 2, objects associated with real estate are arranged in descending order of priority in such a way as not to overlap each other. A balloon display is used (leading lines, such as arrows, can be used) in order to establish associations between real estate icons and objects.